-- AcoustID recording-id lookup (M401). Migration 0069 says what each
-- lookup state means.

-- name: ListTracksNeedingAcoustIDLookup :many
-- The lookup worker's queue: present tracks with no tag MBID and no lookup
-- since their file last changed. A looked-up id is included once its row is
-- gone (the file changed), so the new bytes are checked rather than trusted.
-- Keyset-paged on id, as the loudness queue is, so a pass ends even when
-- every attempt is inconclusive and writes nothing.
SELECT t.id, t.file_path, t.title, t.duration_ms
  FROM tracks t
 WHERE (t.mbid IS NULL OR t.mbid_source = 'acoustid')
   AND t.missing_since IS NULL
   AND t.id > sqlc.arg(after_id)::uuid
   AND NOT EXISTS (SELECT 1 FROM track_acoustid_lookups l WHERE l.track_id = t.id)
 ORDER BY t.id
 LIMIT sqlc.arg(batch_limit);

-- name: RecordAcoustIDLookup :exec
INSERT INTO track_acoustid_lookups (track_id, state, best_score, candidates, recording_mbid, detail)
VALUES (sqlc.arg(track_id), sqlc.arg(state), sqlc.narg(best_score), sqlc.arg(candidates),
        sqlc.narg(recording_mbid), sqlc.narg(detail))
ON CONFLICT (track_id) DO UPDATE SET
    state          = EXCLUDED.state,
    best_score     = EXCLUDED.best_score,
    candidates     = EXCLUDED.candidates,
    recording_mbid = EXCLUDED.recording_mbid,
    detail         = EXCLUDED.detail,
    looked_up_at   = now();

-- name: SetTrackMbidFromAcoustID :execrows
-- Never over a tag id (D4): the guard is here, not only in the worker, so a
-- tag the scan read between the worker's list and this write still wins.
-- updated_at is left alone: it gates the scan's mtime skip, and moving it
-- past a file's mtime would hide a change made just before the lookup.
UPDATE tracks
   SET mbid = sqlc.arg(mbid), mbid_source = 'acoustid'
 WHERE id = sqlc.arg(id)
   AND (mbid IS NULL OR mbid_source = 'acoustid');

-- name: ClearTrackAcoustIDMbid :exec
-- A re-lookup of changed bytes that no longer matches takes back the id an
-- earlier lookup wrote. A tag id is never touched.
UPDATE tracks
   SET mbid = NULL, mbid_source = NULL
 WHERE id = sqlc.arg(id)
   AND mbid_source = 'acoustid';

-- name: DeleteAcoustIDLookup :exec
-- The scan drops the lookup of bytes that are gone, so the worker checks the
-- new ones.
DELETE FROM track_acoustid_lookups WHERE track_id = $1;

-- name: GetMbidCoverage :one
-- The admin gauge: present tracks by where their MBID came from, and the
-- lookup states of those a lookup has seen. pending is what the worker's
-- queue holds.
SELECT count(*)::bigint AS total,
       count(*) FILTER (WHERE t.mbid_source = 'tag')::bigint AS from_tag,
       count(*) FILTER (WHERE t.mbid_source = 'acoustid')::bigint AS from_acoustid,
       count(*) FILTER (WHERE l.state = 'ambiguous')::bigint AS ambiguous,
       count(*) FILTER (WHERE l.state = 'no_match')::bigint AS no_match,
       count(*) FILTER (WHERE l.state = 'failed')::bigint AS failed,
       count(*) FILTER (
           WHERE l.track_id IS NULL AND (t.mbid IS NULL OR t.mbid_source = 'acoustid')
       )::bigint AS pending
  FROM tracks t
  LEFT JOIN track_acoustid_lookups l ON l.track_id = t.id
 WHERE t.missing_since IS NULL;

-- name: ListUnsettledAcoustIDLookups :many
-- The admin list of tracks a lookup could not settle (ambiguous or failed),
-- so they are findable rather than silently empty.
SELECT t.id, t.title, t.file_path, ar.name AS artist_name, al.title AS album_title,
       l.state, l.best_score, l.candidates, l.detail, l.looked_up_at
  FROM track_acoustid_lookups l
  JOIN tracks t ON t.id = l.track_id
  JOIN artists ar ON ar.id = t.artist_id
  JOIN albums al ON al.id = t.album_id
 WHERE l.state IN ('ambiguous', 'failed')
   AND t.missing_since IS NULL
 ORDER BY ar.name, al.title, t.disc_number NULLS FIRST, t.track_number NULLS FIRST, t.title
 LIMIT sqlc.arg(row_limit);

-- name: GetAcoustIDSettings :one
SELECT * FROM acoustid_settings WHERE id = true;

-- name: UpdateAcoustIDSettings :one
-- The key is write-only from the admin card: set_api_key false keeps the
-- stored one, and an empty api_key with set_api_key true clears it.
UPDATE acoustid_settings
   SET enabled    = sqlc.arg(enabled),
       min_score  = sqlc.arg(min_score),
       api_key    = CASE WHEN sqlc.arg(set_api_key)::boolean
                         THEN NULLIF(sqlc.arg(api_key)::text, '')
                         ELSE api_key END,
       updated_at = now()
 WHERE id = true
RETURNING *;